cc: Visualize non-occluding rects in composited layers.

cc: Visualize non-occluding rects in composited layers.

Adds a new flag to show non-occluding rects. When this flag is on, then for any
layer which could have been occluding, but isn't we show a rectangle on the
screen.

This means for layers that have 3d transforms and would never be occluding, we
don't draw rectangles. For axis aligned rectangles with opacity < 1, we don't
draw rectangles.

But when a layer has opacity=1, is axis aligned, but its contents are not
considered opaque, then we draw a rect to warn the user that this area could
have been occluding if only its contents had been considered opaque.

New command-line flag:
--show-nonoccluding-rects

R=jamesr,enne
BUG=160643
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=167816

[danakj, 2012-11-13 03:57:03]

+jam for content/

[jam, 2012-11-13 16:13:12]

lgtm

[danakj, 2012-11-14 19:33:54]

ping @ enne/jamesr

[enne (OOO), 2012-11-14 19:58:26]

lgtm

[commit-bot: I haz the power, 2012-11-14 22:40:20]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/11377122/7001